Incontinence is a familiar and predictable circumstance in the very young. However, the same problem can affect the elderly and/or the infirm of any age, who might have this problem because of some physiological, neurological, or psychological cause. Devices for detecting body fluids such as urine are particularly useful in institutional health care situations, where they are used to monitor and record urinary incontinence in bedfast patients.
As is well known to those of ordinary skill in the art, the trend nation-wide in patient monitoring has been toward the use of electrical devices to signal changes in a patient's circumstance to a care-giver who might be located either nearby or remotely at a central monitoring facility, such as a nurse's station. The obvious advantage of an electronic monitoring arrangement is that it frees the care-giver to pursue other tasks away from the patient. Additionally, when the monitoring is done at a central facility a single nurse can monitor multiple patients which can result in decreased staffing requirements. General information relating to mats for use in patient monitoring may be found in U.S. patent application Ser. No. 09/285,956 filed Apr. 2, 1999 the disclosure of which is specifically incorporated herein by reference. Additionally, U.S. Letters Patent Nos. 4,179,692, 4,295,133, 4,700,180, 5,633,627, and 5,640,145, the disclosures of which are incorporated herein by reference, contain further information generally pertinent to this same subject matter.
Among the advantages of electronic monitoring that are specifically applicable to the invention of the instant disclosure, it is well known that a signalling device can, in some circumstances, serve to condition the wearer to have improved bladder control, which can result in improved attitudes and state of psychological well being. Obviously, timely recognition of a problem has other advantages, including sanitary and aesthetic considerations.
Generally speaking, electronic patient monitors of the sort taught herein work by first sensing an initial status of a patient, and then generating a signal when that status changes, e.g., when the patient's bedclothes--which were formerly dry--become wet due to emission of urine. Electronic enuresis monitors typically exploit the fact that urine is a solution of, among other things, electrolytes, and will conduct a current of electricity. Detecting such fluids often has often involved using a pair of electrodes connected to a voltage source, and a detector circuit that activates an alarm when a gap between the electrodes is bridged by an electrically conductive fluid. Thus, presence of urine completes an otherwise "open" electrical circuit, which fact can be sensed by an attached electronic monitor. Those skilled in the art will recognize that the alarm might be local and/or remote (e.g., the monitor might signal the nurses station that a wetness has been detected).
However, there are serious risks associated with the use of electrical devices to detect fluid emissions, among which is the danger of galvanic burn to the monitored patient. In a typical arrangement, a constant load is applied to two electrical leads that are designed to be electrically isolated until such time as urine is present to bridge the connection. However, since electrical current is undiscriminating in the path that it takes--seeking, as it does, only the most direct way to complete the circuit--it is possible for the electrical current to pass through the patient's body (e.g., along the surface of the skin) when the circuit is completed. Alternatively, and much more dangerously, if the wet patient is grounded a serious electrical shock may be experienced. In spite of this fact, many monitoring pads sold today contain electrically conductive elements that come into near direct physical contact with the monitored individual during the time when those elements carry an electrical charge, thereby creating a risk of a galvanic burn of the patient's skin. Many more pads allow the patient's skin to come into electrical contact with the current used to monitor the device.
Further, many modem electronic monitors are susceptible to false alarms, a false alarm often being generated when the monitor becomes damp, rather than completely wet. Damp conditions might originate from, for example, perspiration. While excessive sweat is certainly a medical condition that could merit triggering an alarm in some instances, it should be under the control of the care giver as to whether or not this condition is signaled. Most electronic monitors are not designed with a minimum triggering wetness threshold level in mind and, thus, are subject to false alarms when they become damp.
Heretofore, as is well known in the patient monitor arts, there has been a need for an invention to address and solve the above-described problems. Accordingly, it should now be recognized, as was recognized by the present inventors, that there exists, and has existed for some time, a very real need for a enuresis mat and monitoring system that would address and solve the above-described problems.
Before proceeding to a description of the present invention, however, it should be noted and remembered that the description of the invention which follows, together with the accompanying drawings, should not be construed as limiting the invention to the examples (or preferred embodiments) shown and described. This is so because those skilled in the art to which the invention pertains will be able to devise other forms of this invention within the ambit of the appended claims.